JPH0899867A - Oil-in-water type nanoemulsion which is useful as vehicle for ophthalmology and its preparation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an oil-in-water type nanoemulsion containing an oil, a nonionic surfactant, benzalkonium chloride, etc., in a specified ratio, having a prescribed transmissivity, a prescribed pH and a prescribed osmotic pressure, increasing the cornea penetration of an active substance, excellent in biocompatibility and useful as an opthalmic vehicle, etc. SOLUTION: This oil-in-water type nanoemulsion comprises (A) 0.1-10 wt./vol.% of an oil such as fractionated fatty acid triglycerides of coconut oil, (B) 0.1-10 wt./vol.% of a nonionic surfactant such as polyoxyethylene- polyoxypropylene copolymer, (C) 0.01 wt./vol.% of benzalkonium chloride as a preservative, (D) 0.1-5 wt./vol.% of a medicine, a medicine precursor or a biologically active substance, such as a glaucoma medicine, and (E) optionally, one or several of the following components: an isotonizing agent, a viscosity- modifying agent or stabilizer, a buffer and/or an antioxidant in variable proportions, and has a transmissivity of <70% measured at 520 nm, a pH of 5-8, and an osmotic pressure of 250-400 mosm/kg.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to the field of drug release by oil-in-water emulsions, particularly for ophthalmic use. The present invention provides a vehicle that increases corneal penetration of the active agent contained in the composition.

[0002]

The most commonly used vehicles for the treatment of eye disorders and diseases are aqueous solutions. However, the aqueous solution applied to the eye is
and the mechanical action of blinking rapidly dilutes and eliminates, mostly lost through the nasolacrimal duct. As described above, most of the administered drug is eliminated before penetrating the cornea and the sclera, which reduces the bioavailability of the drug to the eye. On the other hand, since many of the drugs that can be applied to the eye are of the lipophilic type, they are extremely insoluble in water and therefore they must be applied in the form of suspensions or ointments, and in some cases after application. Causes irritation and discomfort. Moreover, in reality, the drug needs to be dissolved to be absorbed before it is eliminated from the surface of the eye, which reduces bioavailability in the case of suspension.

Other types of vehicles have been developed to increase the residence time of the drug on the surface of the eye. Among these, the vehicle with improved biocompatibility by increasing the viscosity is like hydrogel or ophthalmic ointment. In the case of hydrogels, no satisfactory improvement in the bioavailability of the drug has been obtained. Its use is preferred at night because some ophthalmic ointments are very cumbersome to apply and have blurred eyes after application. Similarly, numerous new vehicles such as liposomes, nanoparticles, etc. have been developed, but most of them are stable, tolerant, and difficult to industrialize, although with considerable success in bioavailability. I have a problem.

Different types of emulsions have been proposed as vehicles for ocular drug release. Among these, European Patent Application 0 521 799 Al describes an oil-in-water emulsion for the release of hydrophobic, amphoteric and lipophilic drugs. The composition includes an oil, a phospholipid and an amphoteric surfactant. Although the role of phospholipids is essential for the stability of the emulsions of this invention, phosphatidylcholine and its derivative, lysophosphatidyl, are essentially cataracts.
have been described by other authors [(1) "Effects of lysophosphatidylcholine and phospholipase A on the lens (Effects of l
ysophosphatidyl choline an
d phospholipase A on the le
ns ”, Cotlier, E.
), Baskin, M. and Kresca, L., Investigative Offtalmology.
e Ophthalmology), Volume 14, Volume 9
Issue: pp. 697-701 (1975). (2) "Phospholipid Effects on the Rat Lens Transport Systems (Phospholipid
effects on the rat lens tr
"Ansport Systems"; Kader, P. F. and Kinoshita, K. Shino, J. H., Experiential Eye Research (Exp. EyeRe)
s.) 26, pp. 657-665 (1978).
Year)〕.

On the other hand, health authorities in most countries require the use of preservatives in ophthalmic products. This patent describes thimerosal-chlorobutanol,
It is not effective if used separately, so 0.01
It is claimed to be used in combination at a concentration of ˜0.2% (weight / volume) and in combination with benzalkonium chloride at a concentration of 0.02% (weight / volume) when used alone.

The present invention provides ophthalmic formulations in the form of nanoemulsions which are stable over time without the inclusion of phospholipids in the composition. The subject formulations of the present invention, on the other hand, meet the criteria of the European, British and US Pharmacopoeias, which use up to 0.01% (weight / volume) of benzalkonium chloride.

US Pat. No. 5,171,566 also discloses an oil-in-water emulsion, which contains soybean oil and soybean lecithin as emulsifiers. In addition to lecithin, this type of emulsion also contains phosphatidylcholine and therefore may have the same problems of toxicity described above. Similarly, they contain other stabilizers such as cholesterol or phosphatidylic acid. The emulsion is either lyophilized or kept at 4 ° C. This composition has the same disadvantages as the above-mentioned patent and contains only flurbiprofen and its esters. Unlike the present invention, it does not claim or describe the effect of improving bioavailability, but rather limits it to mention the presence of the drug in the body fluids of rabbits. On the other hand, we have observed that the nanoemulsions of the invention can increase the bioavailability of the drug in the eye by about 4-fold.

European patent application 0 480 690 Al describes emulsion type ophthalmic products, but deals with products which are substantially different from those of the present invention. The above-mentioned application discloses tepoxaline which has a translucent or transparent appearance, which is a characteristic peculiar to a microemulsion having an oil droplet size of 0.005 to 0.5 μm.
Is claimed for the preparation of the microemulsion. This appearance severely limits its industrial productivity. The nonionic surfactant used is a polysorbate (polysorb).
and the concentration of the preservative (s) is 0.02 to 0.7%
(Weight / volume). The present invention deals with different compositions because instead of microemulsions they are nanoemulsions which are neither transparent nor translucent (transmittance at 520 nm <70%). Similarly, the amount of preservative used is much less at this concentration than that used in the aforementioned patents where preservative toxicity is a concern.

[0009]

The object of the present invention is to improve the bioavailability by keeping the preservative at a low concentration, which is required by the pharmacopoeial standards of many countries but has a considerable toxic effect on the eyes. It is to provide a vehicle that is useful for ophthalmology.

The present invention provides an oil-in-water emulsion type formulation which is highly bio-applicable to the pharmaceutical eye in a vehicle. This emulsion contains a cataract as in the case of potentially irritating products and lecithin in its composition.
It is stable during storage without the inclusion of products that cause artogenic processes. Also, according to the formulations of the present invention, preservatives (benzalkonium chloride) in small amounts can be used in other types of formulations described above that do not meet the Pharmacopoeia standards for ophthalmic products. On the other hand, the emulsions of the present invention can be obtained using conventional emulsifying equipment such as rotary stirrers or other pressure homogenizers.

Although most national health regulations require the inclusion of preservatives in multidose type ophthalmic products, in practice all preservatives used are of considerable toxicity to the eye. It has an effect. Therefore, having an ophthalmic vehicle in which preservatives can be used in low concentrations represents a very important advantage for ophthalmic formulation safety. As described above, the present invention provides 0.01 to 0.
2% (weight / volume) chlorobutanol and 0.01-0.0.
Claims the combined use of 2% (weight / volume) thimerosal (0.02% benzalkonium chloride due to its ability to interact with surfactants or absorption into the oil used). Unlike the one described in European patent application 0 521 799 Al (since weight / volume has no effect), a preservative (0.005-0.01%
Provided is an ophthalmic vehicle capable of using a low concentration of (weight / volume benzalkonium chloride).

[0012]

SUMMARY OF THE INVENTION In the present invention, an oil-soluble or partially oil-soluble drug is included in an oil-in-water emulsion to be administered to the eye so that it is better than other compositions. Its bioavailability is enhanced. The vehicle contains oils and nonionic surfactants, and preservatives sufficient to meet Pharmacopoeia standards. The oils which form part of the emulsion may be vegetable oils, animal oils, mineral oils, fatty acids, medium chain triglycerides, fatty alcohols or any combination of well-tolerated oils and oils.

Most preferred oils are medium chain triglycerides, due to their high solubility in water, their density, their insensitivity to oxidation, and their excellent tolerance in the eye. Among these, fractionated C _8-10 fatty acid triglycerides of coconut oil, and C _8-10
Propylene glycol esters of medium chain saturated fatty acids are excellent. Polyethylene glycol esters and glycerides should also be mentioned. As vegetable oils, olive oil, sunflower seed oil, and sesame oil with acid numbers less than 0.5 are worth taking. The oil is preferably 0.1 to 10% (weight / volume) in the composition of the present invention.

Examples of nonionic surfactants are polyoxyethylene-polyoxypropylene copolymers, preferably polyoxamer 188 and polyoxamer 407. 10% of these surfactants when administered to the eye
Even the (weight / volume) concentration is very tolerant, there is no irritation to the eyes and no damage. By using these surfactants at appropriate concentrations, the nanoemulsion can be kept stable without using other cosurfactants.
The preferred concentration of nonionic surfactant for the compositions of the present invention is 0.1-10% (weight / volume).

The composition of the present invention may contain another medicament used in ophthalmology. Examples of anti-glaucoma drugs include carteolol base, betaxolol, atenolol,
Mention may be made of carbonic anhydrase inhibitors such as timolol base and metazolamide. Examples of antibiotics include chloramphenicol, and examples of anti-inflammatory agents include indomethacin, piroxicam, dichlorophenacic acid, ibuprofen, dexamethasone and clobetasone. Other types of drugs are cyclosporin A, acyclovir and acid cromoglycate. Depending on the nature of the oil, the composition of the present invention may include an antioxidant to prevent oxidation of the oil.

The compositions of the present invention include isotonic agents such as mannitol, glycerol, sorbitol or glucose; viscosity modifiers such as hydroxypropylmethyl cellulose, polyacrylic acid derivatives or sodium carboxymethyl cellulose; sodium edatate.
stabilizers such as sodium phosphate and citric acid; buffering agents such as sodium or potassium phosphate, sodium citrate, sodium carbonate and sodium bicarbonate. Stabilizing the composition of the present invention by using a polyacrylic acid polymer at a concentration between 0.1-0.5% (weight / volume) to cream the aggregation and phase separation of oil droplets. You can even avoid it. These compositions have an apparent white gel-like appearance with a certain viscosity.

As stated above, the present invention provides an oil-in-water nanoemulsion useful as an ophthalmic vehicle, characterized in that it comprises: (a) about 0.1-10% (weight / weight). Volume of oil (b) about 0.1-10% (weight / volume) nonionic surfactant (c) about 0.01% (weight / volume) or less,
Benzalkonium chloride (d) as a preservative (d) 0.01-5% (weight / volume) drug, drug precursor or biologically active substance (e) One or several of the following components as optional components : Varying amounts of isotonic agents; viscosity modifiers; stabilizers, buffers and / or
Or an antioxidant.

The emulsion of the invention has a transmittance of less than 70% measured at 520 nm, a pH of between 5 and 8 and an osmolarity of 250 to 400 mOsm / kg.
The appearance of these emulsions is thin milky. The composition of the present invention may be sterilized by filtration so long as it can form oil droplets, or may be sterilized in the state of an aqueous phase and an oil phase and then mixed and emulsified depending on the state of appearance.

Contrary to what might be expected, the drug contained in the composition of the invention penetrates through the cornea up to 6 times more than the same drug in aqueous solution in the "in vitro" experimental model. . Similarly, when the composition of the invention is instilled in the rabbit, the amount of the "in vivo" level of the drug in the aqueous body fluid will be approximately four times higher than would be obtained with an aqueous solution of the same drug. This increased bioavailability often means great benefit because the daily infusion or dosage of these medications used to treat chronic eye diseases can be reduced.

The composition of the invention may be prepared in different ways. One method involves preparing the aqueous and oil phases separately. The aqueous phase contains suitable proportions of nonionic surfactants, isotonicity agents, preservatives and pH buffering systems. The oily phase contains all and part of the active substance dissolved in the oil and may contain antioxidants. To prepare the emulsion, the oil phase is added to the aqueous phase under moderate agitation and then an ultra-turrax type homogenizer (junk and kunkel until a mean particle size of less than 5 μm is obtained. (Janke and F
unkel), Staufen,
Germany] to reduce the particle size. Oil droplets of this size can also be obtained using a high pressure homogenizer or any device capable of reducing particle size appropriately.

According to another particular method of preparation of the invention, the product is normally exposed to temperatures of 45 to 85 ° C. which influence the heat-sensitive active substance or influence the oxidation and decomposition reactions of the components of the formulation. Unlike the temperature of 1), an oil-in-water emulsion having an average oil droplet size of 200 nm can be obtained at a temperature of 35 ° C or lower.

This method of preparation comprises preparing an aqueous phase as above and an organic phase containing the oil and the active substance which is wholly or partially soluble in the oil, both of which are acetone. , Readily soluble in water, such as ethanol or tetrahydrofuran, and soluble in organic solvents having a dielectric constant greater than 15. The above organic phase is added to the aqueous phase under moderate agitation, and the organic solvent and a part of water are evaporated under reduced pressure in an applicable evaporation system.
Removal at temperatures below ° C gives a very fine and uniform emulsion.

[0023]

The invention is further illustrated by the following examples, which do not limit the scope of the claims.
The product trade name is used in the description of the examples.
It should be considered that the product can be any product with the same characteristics that is commercially available from other companies. The product is: "Miglyol 812" [registered trademark; Dynamit Nob
El), Sweden]: C separated from coconut oil
Triglycerides of _{8 to} C ₁₀ fatty acids. "Edenor SbO ₅ " [registered trademark;
Henkel, Düsseldorf]: A mixture of saturated and unsaturated fatty acids whose main constituent is oleic acid (67%). "Lutrol F68" [registered trademark; B
ASF, Germany]: polyoxyethylene-polyoxypropylene copolymer, poloxam.
er) 188. In all of the formulations below, the two phases are sterilized separately to prepare emulsions aseptically, or the final product is sterile filtered through a 0.22 μm filter.

Example 1: Miglyol 812 (registered trademark )
Nanoemulsion mark) (Emarujo emissions A) nonionic surfactant (Lutrol F68 (R))
10 g is added to 500 ml deionized water. To this solution is added 15 ml of oil (Miglyol 812®). It is then passed through an Ultra-Turrax homogenizer (Junk & Kunkel, Staofen, Germany) for 20 minutes at 10,000 rpm to emulsify it and obtain a nanoemulsion with a particle size of less than 0.5 μm. 0.25 g of disodium edetate (stabilizer), 2
7.4 g sorbitol powder (isotonic agent) and 0.05 g
Of benzalkonium chloride (preservative) is added to this emulsion.

The concentrations of the resulting solutions are as follows: Lutrol F68®: 2.00% (weight / volume) Miglyol 812®: 3.00% (volume / volume) disodium ede. Tate: 0.05% (weight / volume) Sorbitol powder: 5.48% (weight / volume) Benzalkonium chloride: 0.01% (weight / volume) Add deionized water to make a total volume of 100 ml. Zetasizer 3 [Malvern Instruments]
Company, United Kingdom], the average particle size of the oil droplets was 230n
The polydispersity in m was 0.220.

Example 2: Miglyol 812 (registered trademark )
Except adding 20g nanoemulsion (Emarujo emissions B) Lutrol F68 in mark) instead of adding 10g was conducted according to the method described in Example 1. The resulting concentrations are as follows: Lutrol F68®: 4.00% (weight / volume) Miglyol 812®: 3.00% (volume / volume) Disodium edetate: 0.05 % (Weight / volume) Sorbitol powder: 5.48% (weight / volume) Benzalkonium chloride: 0.01% (weight / volume) Deionized water is added to make a total volume of 100 ml. As a result of measurement with Zetasizer 3, the average particle size of the oil droplets was 237 nm, and the polydispersity was 0.241.

Example 3: Carteolol Base 0.2
% Nanoemulsion (Emulsion C) Lutrol F68® 8 g is added to 190 ml deionized water and the whole solution is filtered at 0.22 μm (aqueous phase). Separately, 0.44 g of carteolol base is weighed, to which 0.2 g of edenol SbO ₅ and 2.0 g of Miglyol 812® are added. Gently heat until a carteolol based solution is obtained (oil phase). The oil phase is added to the aqueous phase while stirring with a magnetic stirrer, which is then passed through an Ultra-Turrax homogenizer at 10,000 rpm for 10 minutes until a nanoemulsion with a particle size smaller than 0.5 μm is obtained. The nanoemulsion thus obtained has a basic pH,
Neutralize to pH = 7.4 with 0.1N hydrochloric acid solution. To isotonize the emulsion, 10.14 g of apyrogenic mannitol are added to it, followed by 2 ml of a 1% (weight / volume) benzalkonium chloride solution. Finally, add deionized water to 20
Make up to 0 ml and finish.

The final concentrations are as follows: Lutrol F68®: 4.00% (weight / volume) Miglyol 812®: 1.00% (weight / volume) Edenol SbO ₅ : 0.00 10% (weight / volume) Carteolol base: 0.22% (weight / volume) Apyrogenic mannitol 5.07% (weight / volume) Benzalkonium chloride: 0.01% (weight / volume) deionized water Is added to bring the total volume to 100 ml. As a result of measurement with Zetasizer 3, the average particle size of the oil droplets was 272 nm, and the polydispersity was 0.273.

Example 4: Indomethacin 0.1% Na
0.26 μ of 1.66 g of Noemulsion (Emulsion D) Lutrol F68 (registered trademark)
Dissolve in 190 ml of deionized water filtered through m (aqueous phase). Indomethacin 0.05g and Miglyol 8
0.5 g of 12® is dissolved in 50 ml of acetone (organic phase). Add the organic phase to the aqueous phase while stirring at 500 rpm with a magnetic stirrer. The resulting dispersion is evaporated on a rotary evaporator under reduced pressure and at a temperature below 35 ° C. until all the acetone and some of the water have been removed and the final volume is 40 ml. 2.53 g to make it iso-pressurized
1% as an antiseptic by adding aprogenic mannitol
Add 0.50 ml (weight / volume) benzalkonium chloride. To this, 0.0025 g of crystallized monopotassium phosphate and 0.1128 g of crystallized disodium phosphate dodecahydrate were added and dissolved to prepare a buffering agent.
Adjust H to 7. Also add 0.0275 g of disodium edetate as a stabilizer and add deionized water to 5
Make up to 0 ml.

The concentration of what is obtained is as follows: Lutrol F68®: 3.320% (weight / volume) Miglyol 812®: 1.000% (weight / volume) Indomethacin: 100% (weight / volume) Aprogenic mannitol: 5.070% (weight / volume) Crystalline monopotassium phosphate: 0.005% (weight / volume) Crystalline disodium phosphate dodecahydrate: 0.221% ( Weight / volume) Disodium edetate: 0.055% (weight / volume) Benzalkonium chloride: 0.010% (weight / volume) Add deionized water to make a total volume of 100 ml. As a result of measurement with Zetasizer 3, the average particle size of the oil droplets was 280 nm and the polydispersity was 0.250.

Example 5: Miglyol 812 (registered trademark )
Lutrol nanoemulsion gel (of 0.10g of deionized water Emma Rujon E) 15 ml of mark) F68
® is added and the whole solution is filtered through 0.22 μm. Stir this solution with a magnetic stirrer.
Add 20 ml of Miglyol 812®.
The resulting dispersion is then emulsified in an Ultra-Turrax homogenizer at 10,000 rpm for 15 minutes to give a nanoemulsion with a particle size of less than 0.5 μm. To this emulsion are added 1.014 g of aprogenic mannitol and 0.2 ml of a 1% (weight / volume) solution of benzalkonium chloride. To finish the formulation, the Carbopol 940 previously prepared at 0.
Add 5 g of 6% gel. Stir with a glass rod until a gel of the desired viscosity is obtained.

The concentrations of the preparations are as follows: Lutrol F68®: 0.50% (weight / volume) Miglyol 812®: 1.00% (weight / volume) Aprogenic mannitol : 5.07% (weight / volume) Benzalkonium chloride: 0.01% (weight / volume) Carbopol 940: 0.15% (weight / volume) Add deionized water to make a total volume of 100 ml . As a result of measurement with Zetasizer 3, the average particle size of the oil droplets was 278 nm, and the polydispersity was 0.259.

Example 6: Miglyol 812 (registered trademark )
Standard) nanoemulsion (Emulsion F) 4.00 g Lutrol F6 in 190 ml deionized water
8® is added and the whole solution is filtered through 0.22 μm. Once dissolved, the resulting aqueous phase is placed in a 70 ° C. water bath. At that temperature add 6.00 ml of Miglyol 812®. The resulting dispersion is 1 until an emulsion with a particle size of less than 0.5 μm is obtained.
Apply to Ultra-Turrax homogenizer for 15 minutes at 0,000 rpm. Then 10.96 g sorbitol flour, 0.10 g disodium edetate and 1%
Add 1 ml (weight / volume) concentration of benzalkonium chloride. Finally, make up the volume to 200 ml with deionized water.

The final concentrations are as follows: Lutrol F68®: 2.000% (weight / volume) Miglyol 812®: 3.000% (weight / volume) Sorbitol powder: 5.480 % (Weight / volume) Disodium edetate: 0.050% (weight / volume) Benzalkonium chloride: 0.005% (weight / volume) Add deionized water to make a total volume of 100 ml. As a result of measurement with Zetasizer 3, the average particle size of oil droplets is 224.3n.
The polydispersity in m was 0.175.

Example 7: Miglyol 812 (registered trademark )
Lutrol 0.5g of the nanoemulsion (Emarujo emission G) deionized water 90ml of target) F68
® is added and the whole solution is filtered through 0.22 μm. Once dissolved, the resulting aqueous phase is placed in a 70 ° C. water bath. When that temperature is reached, add 1.00 ml of Miglyol 812®. The resulting dispersion was made 10, until an emulsion with a particle size of less than 0.5 μm was obtained,
Apply to Ultra-Turrax homogenizer at 000 rpm for 10 minutes. Then 5.48 g of sorbitol powder and 1 ml of 1% (weight / volume) concentration of benzalkonium chloride
Add. Then make up to 10 ml volume with deionized water.

The final concentrations are as follows: Lutrol F68®: 0.50% (weight / volume) Miglyol 812®: 1.00% (weight / volume) Sorbitol powder: 5.48 % (Weight / volume) Benzalkonium chloride: 0.01% (weight / volume) Add deionized water to make a total volume of 100 ml.

Stability Evaluation The stability of Emulsion A and Emulsion B kept at different temperatures was followed. Controls are run for different times,
The oil droplet average particle size results are shown in FIGS. 1 and 2, and the polydispersity results are shown in FIGS. 3 and 4. The pH results are shown in Figures 5 and 6. No significant changes were observed in any of the three parameters throughout the evaluation period. In the nanoemulsion C containing carteolol base, the active substance content was confirmed in addition to the above parameters. Average particle size results are shown in FIG. 7, polydispersity results in FIG. 8 and pH results in FIG. The results of the active substance content are shown in FIG. No significant changes in physical-chemical parameters have been observed. As seen in FIG. 10, the freezing temperature,
There is no change in the carteolol base concentration during storage at any temperature of room temperature 35 ° C and 5-45 ° C (alternate temperature).

Studies on the Acute Ocular Concentration of Rabbits New Zealand albino rabbits were repeatedly infused with 50 μl of emulsion B and emulsion D every 6 hours for 20 minutes, and the acute ophthalmic concentration of these emulsions was used as a salt solution as a control. Evaluated. Tolerable concentrations for the eyes were evaluated by blinking, redness, edema, exudates and disorders in the iris and cornea 24 hours after application was completed. The results show that emulsions B and D have a normal eye irritation index.

The corneal permeation penetration of indomethacin contained at a concentration of 0.1% (weight / volume) in the “in vivo” corneal permeation nanoemulsion D was evaluated and it was determined to be 0.1% (weight / volume) in aqueous solution. Compared with the permeation of indomethacin contained in concentration. To this end, the rabbit cornea was cut with Diez-Noguer.
a) etc., “Corneal permeation penetration chamber (Transc
oral Penetration Chamber
r) LC-100 "[(3) Dies-Noguera A., Igual A. and Guzma El.
nL.), “Design of an“ In vitro ”
・ System for Pharmacokinetic Studies (Design of an “in vitro”)
system for pharmacokineti
c studies, Laboratories Kushi, Labs. Cusi, S.A., El Masnous, Barcelona (Bar)
Celona), Catalonia,
Spain, 7th edition, International Congress of Eye Research (International C
ongress of Eye Research, Nagoya, Japan (1986)] (FIG. 11). The coating surface of the cornea was exposed to the test product for 3 hours. 200 μl of an aliquot of artificial body fluid (AAH) was added to 15, 30, 6
It was withdrawn from the rear of the chamber after 0, 120, 150 and 180 minutes. The Wach sample was immediately replaced with an equal volume of AAH.

The indomethacin content of the samples was measured immediately after extraction by HPLC and at 250 nm and the values obtained were used to calculate the permeability coefficient (P, in cm / s). INDO: 0.1% (weight / volume) indomethacin solution NAND: Nanoemulsion D The results are shown graphically in FIG.

The permeation coefficient is expressed by the equation of Glass and Robinson [(4) Grass GM]
And Robinson J. Earl (Robinson)
JR), Journal of Pharmaceutical Sciences (Journal of Pharm)
acoustic Sciences), Volume 77,
No. 1, pp. 3-14 (1988)]

[Equation 1] In the formula, Δt / Δc: slope of the linear portion of the graph 3: volume of the back surface of the chamber expressed in ml 60: conversion coefficient from minutes to seconds A: corneal surface exposed to product (0.721 cm ² ) Co: Calculated using theoretical concentration of test product. The incubation time was obtained by extrapolating the linear part of the graph. As can be seen from FIG. 12, indomethacin in the nanoemulsion penetrates earlier and more than when in solution.

In Vivo Pharmacokinetic Studies Pigmented Rabbits
[Fauver de Bourgonju (Fauver de
Bourgon)] and nanoemulsion D and 0.1
% (Weight / volume) of indomethacin in water
5 μl each was instilled once. 15 minutes, 30 minutes, and 1, 2 after instilling about 200 μl of aqueous body fluid from the front chamber
Samples were taken at 4, 6 and 8 hours. Aqueous body fluid sample
It was filtered through a 45 μm filter and analyzed by HPLC immediately after collection and at 250 nm. The obtained results are shown in Table 1.

[0043]

[Table 1]

The results are shown graphically in FIG. Figure 1
As can be seen from 3, experimental data show that permeation of indomethacin in Nanoemulsion D is significantly increased compared to the aqueous solution. Similarly, the expression of indomethacin in the body fluid was longer than the detection limit in Nanoemulsion D by 2 hours as compared with the case of the aqueous solution.

Storage Efficacy Studies Bacteria were placed in tryptose-soybeans in an oven at 34 ° C.
It was cultured for 8 hours. Candida albicans and Alpergillus niger were cultured in Sabouraud culture medium in a 22 ° C. oven for 48 hours and 7 days, respectively. A suspension of about 1 × 10 ⁸ ufc / ml was prepared from the culture medium. 20 ml of each nanoemulsion (A, F and G)
200 μl of each microbial suspension was added to the tube containing.
The microbial ufc contained in 1 ml of the nanoemulsion at 0, 6, 24 hours and 7, 14 and 28 days was counted. In addition, microorganisms in physiological saline were counted as inoculum controls, and sterilized controls of uninoculated media were counted. For each 1 ml of each nanoemulsion, and for each test time, added 0.1 to neutralize the preservative.
A series of dilutions (1/19) diluted with Leethan broth containing 5% (weight / volume) Tween 80 were prepared. 1 ml of each dilution
Were melted at 45 ° C. and cultivated in triplicate in 20 ml of tryptose agar soybean supplemented with 0.5% (weight / volume) Tween 80.

Nanoemulsions A and F are Europa
Pharmacopeia 1993 (Euroean Pha
rmacopoea 1993 (criteria B) and British Pharmacopeia 1993 (Br
Tissue Pharmacopoeia 1993) (Criterion B); Pharmacopoe Francaise 198
9) and USP, Vol. 22, 19
Meets 90-year regulations. Nanoemulsion G, which contains less surfactant, is also available in Yuropian Pharmacopeia 1
Meets 993 (criteria A) and British Pharmacopeia 1993 (criteria A). Thus, the nanoemulsions of the present invention have much lower preservative concentrations than are used in other oil-in-water emulsions and meet most important Pharmacopoeia standards. The latter other oil-in-water emulsions do not meet the standards of the Pharmacopoeia in terms of preservative effect when the preservative concentrations used in the formulations of the invention are used. The results are shown in Tables 2, 3 and 4.

[0047]

[Table 2]

[0048]

[Table 3]

[0049]

[Table 4]

[0050]

[Brief description of drawings]

FIG. 1 is a graph showing the stability of emulsion A over time, expressed as the average oil droplet size in nm.

FIG. 2 is a graph showing the stability of emulsion B over time, expressed as the average oil droplet size in nm.

FIG. 3 is a graph showing changes in polydispersity of emulsion A with time.

FIG. 4 is a graph showing the polydispersity of Emulsion B over time.

FIG. 5 is a graph showing the time change of pH of emulsion A.

FIG. 6 is a graph showing the time change of pH of emulsion B.

FIG. 7 is a graph showing the stability of emulsion C over time, expressed as the average oil droplet size in nm.

FIG. 8 is a graph showing the polydispersity of Emulsion C over time.

FIG. 9 is a graph showing the time change of pH of emulsion C.

FIG. 10 is a graph showing the change over time in the amount of active substance released in emulsion C expressed as a percentage of the initial theoretical content.

FIG. 11: Diagram of the corneal permeation device (model LC-100) used in the “in vitro” test.

FIG. 12 is a graph showing corneal permeation penetration of indomethacin in Nanoemulsion D, showing the concentration of indomethacin against time.

FIG. 13. “In Vivo” for Nanoemulsion D
FIG. 4 is a graph showing the pharmacokinetics of the drug, showing the concentration of indomethacin in the colored aqueous body fluid of the rabbit over time.

[Explanation of symbols]

1: Corneal permeation and penetration chamber 2: Constant temperature water bath (37 ° C) 3. Carbon generation tank (95% O ₂ and 5% CO ₂ ) 4. Omniscrib D-5000 recorder 5. Platinum-calomel electrode 6. Agarose: KCl bridge 7. Amplifier 8. Peristaltic pump 9. Magnetic stirrer 10. Artificial tear solution / test product

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical indication location A61K 31/405 31/47 31/52 31/54 31/57 38/00 (72) Inventor Anna・ Cole Dux Spain 08012 Grand de Gracia 47 Barcelona Quart Primera (72) Inventor Nuria Carreras Perdiger Spain 08140 Caldes de Montbui (Barcelona) Amadeo Vivez 6 (Urbano Els Saulons) )

Claims (18)

[Claims] 1. The following: (a) about 0.1-10% (weight / volume) oil (b) about 0.1-10% (weight / volume) nonionic surfactant (c) About 0.01% (weight / volume) or less,
Benzalkonium chloride as a preservative (d) about 0.01-5% (weight / volume) of a drug, a drug precursor or a biologically active substance (e) optionally one or several of the following: Ingredients: Isotonicity agent; Viscosity modifier; Stabilizers, buffers and / or various amounts of antioxidants, with a transmittance of less than 70% measured at 520 nm and a pH between 5 and 8 An oil-in-water nanoemulsion useful as an ophthalmic vehicle, which has an osmotic pressure of 250 to 400 mOsm / kg. 2. The nanoemulsion according to claim 1, wherein the oil is a fractionated fatty acid triglyceride of coconut oil, a mixture of fatty acids or a propylene glycol ester of saturated vegetable fatty acids. 3. The nanoemulsion according to claim 1, wherein the nonionic surfactant is a polyoxyethylene-polyoxypropylene copolymer. 4. The nonionic surfactant is a poloxamer (p
4. The nanoemulsion according to claim 3, which is an oloxamer. 5. The nanoemulsion according to claim 1, which contains a drug selected from an anti-glaucoma drug, an antibiotic, an antibiotic allergy drug, an antiviral drug, and an anti-inflammatory drug. 6. The anti-glaucoma drug is carteolol base (c
arteololbase), betaxolol (bet
A nanoemulsion according to claim 5, which is selected from among axolol, atenolol and timolol base. 7. The anti-inflammatory drug is indomethacin (indom).
Ethacin), piroxicam (pyroxyca)
m), dichlorophenacic acid (dichlofenac)
acid), ibuprofen
n), dexamethasone
The nanoemulsion according to claim 5, which is selected from among clobetasone and clobetasone. 8. The medicine is cyclosporin.
The nanoemulsion according to claim 5, which is porin) A. 9. The medicine is acyclovir.
The nanoemulsion according to claim 5, which is ovir). 10. The drug is an acid chromoglygate.
The nanoemulsion according to claim 5, which is a chromoglygate). 11. The nanoemulsion according to claim 1, wherein the isotonic agent is selected from mannitol, glycerol, sorbitol and glucose. 12. The nanoemulsion according to claim 1, wherein the viscosity modifier is selected from hydroxyopropylmethyl cellulose, polyacrylic acid derivatives and sodium carboxymethyl cellulose. 13. The nanoemulsion according to claim 1, wherein the stabilizer is selected from ethylenediaminetetraacetic acid sodium salt and citric acid. 14. The nanoemulsion according to claim 1, wherein the buffering agent is selected from sodium phosphate, potassium phosphate, sodium citrate, sodium carbonate and sodium bicarbonate. 15. The nanoemulsion according to claim 1 or any one of claims 5 to 10, characterized in that the drug, drug precursor or biologically active substance is partially or wholly dissolved in the oil. . 16. Benzalkonium chloride is 0.005%
The nanoemulsion according to claim 1, which is found at a concentration equal to or higher than (weight / volume). 17. The nanoemulsion according to claim 1, which increases the permeation of the drug, drug precursor or biologically active substance in the vehicle into the eye by a factor of 2 or more. 18. Preparation of an aqueous phase containing nonionic surfactants, isotonic agents, preservatives, buffers and viscosity modifiers, if present; oils and whole or partly in oils. Preparation of an oil phase containing the solubilized active substance and, if present, an antioxidant; and, after addition of the oil phase to the aqueous phase under moderate stirring, averaged by a homogenizer to obtain an average particle size of about 500 nm. (1) preparing an organic phase containing an active substance and an oil instead of the above oil phase, wherein the active substance is wholly or partially solubilized in the oil. (Active substance and oil) easily miscible in water and dissolved in an organic solvent having a dielectric constant greater than 15, and (2) after adding the above organic phase to the aqueous phase under moderate stirring, Under reduced pressure and 3
The organic solvent and a part of water are removed at a temperature of 5 ° C. or lower to obtain a very fine and uniform emulsion containing a considerable amount of oil droplets having an average particle size of about 200 nm. A method for preparing an oil-in-water nanoemulsion useful as an ophthalmic vehicle, as described in 1.